To select a specific column from a table using php postgres - php

Question

I have table of 5000+ rows and 8+ columns like,
Station Lat Long Date Rainfall Temp Humidity Windspeed
Abcd - - 09/09/1996 - - - -
Abcd - - 10/09/1996 - - - -
Abcd - - 11/09/1996 - - - -
Abcd - - 12/09/1996 - - - -
Efgh - - 09/09/1996 - - - -
Efgh - - 10/09/1996 - - - -
Efgh - - 11/09/1996 - - - -
Efgh - - 12/09/1996 - - - -
I am developing a web application, in that user will select a column like rainfall/temp/humidity and for a particular date.
Can anyone guide me how to query for this in php-postgres. (database:postgres, table:weatherdata, user:user, password:password)
Thanks in advance.

Answer 1

You can use some code like this:
public function getData ($date, $columnsToShow = null) {
/* You could check the parameters here:
* $date is string and not empty
* $columnsToShow is an array or null.
*/
if (isset ($columnsToShow))
$columnsToShow = implode (',', $columnsToShow);
else $columnsToShow = "*";
$query = "select {$columnsToShow}
from table
where date = '{$date}'";
$result = array();
$conex = pg_connect ("host=yourHost user=yourUser password=yourUser dbname=yourDatabase");
if (is_resource ($conex)) {
$rows = pg_query ($conex, $query);
if ($rows) {
while ($data = pg_fetch_array ($rows, null, 'PGSQL_ASSOC'))
$result[] = $data;
}
}
return (empty ($result) ? null : $result);
}
Now you can invoke, for example, like this:
getData ('2012-03-21', array ('Station', 'Rainfall'));
I hope you serve.